Technical Field
The present disclosures relate to an image processing apparatus and an image processing method.
Related Art
A binarizing process is known as one of image processing to be applied to image data. In the binarizing process, each of pixels constituting image data (e.g., multi-value image data) expressed in multi steps (e.g., 256 steps) of gradation expression is converted into a white pixel having a gradation value representing a white color, or a black pixel having a gradation value representing a black color by comparing the value of each pixel with a threshold value. As a result of the binarization of each pixel, image data consisting of white and black pixels (i.e., binarized image data) is generated. The binarizing process may be executed, for example, to reduce the size of the image data, or as a pre-process for a particular image processing (e.g., a character recognition using an OCR function).
Conventionally, in order to obtain good results in the binarizing process, there is known a technique to determine the threshold value to be referred to in the binarizing process based on a histogram of gradation values of respective pixels constituting the image data.